Hospitalizations because of adverse drug reactions in elderly patients admitted through the emergency department: a prospective survey

Prevalence and differences in the co-administration of drugs known to interact: an analysis of three distinct and large populations

BACKGROUND

The co-administration of drugs known to interact greatly impacts morbidity, mortality, and health economics. This study aims to examine the drug-drug interaction (DDI) phenomenon with a large-scale longitudinal analysis of age and gender differences found in drug administration data from three distinct healthcare systems.

METHODS

This study analyzes drug administrations from population-wide electronic health records in Blumenau (Brazil; 133 K individuals), Catalonia (Spain; 5.5 M individuals), and Indianapolis (USA; 264 K individuals). The stratified prevalences of DDI for multiple severity levels per patient gender and age at the time of administration are computed, and null models are used to estimate the expected impact of polypharmacy on DDI prevalence. Finally, to study actionable strategies to reduce DDI prevalence, alternative polypharmacy regimens using drugs with fewer known interactions are simulated.

RESULTS

A large prevalence of co-administration of drugs known to interact is found in all populations, affecting 12.51%, 12.12%, and 10.06% of individuals in Blumenau, Indianapolis, and Catalonia, respectively. Despite very different healthcare systems and drug availability, the increasing prevalence of DDI as patients age is very similar across all three populations and is not explained solely by higher co-administration rates in the elderly. In general, the prevalence of DDI is significantly higher in women - with the exception of men over 50 years old in Indianapolis. Finally, we show that using proton pump inhibitor alternatives to omeprazole (the drug involved in more co-administrations in Catalonia and Blumenau), the proportion of patients that are administered known DDI can be reduced by up to 21% in both Blumenau and Catalonia and 2% in Indianapolis.

CONCLUSIONS

DDI administration has a high incidence in society, regardless of geographic, population, and healthcare management differences. Although DDI prevalence increases with age, our analysis points to a complex phenomenon that is much more prevalent than expected, suggesting comorbidities as key drivers of the increase. Furthermore, the gender differences observed in most age groups across populations are concerning in regard to gender equity in healthcare. Finally, our study exemplifies how electronic health records' analysis can lead to actionable interventions that significantly reduce the administration of known DDI and its associated human and economic costs.

Patients' Characterization, Pattern of Medication Use, and Factors Associated with Polypharmacy: A Cross-Sectional Study Focused on Eight Units of the Portuguese National Network for Long-Term Integrated Care

The Portuguese National Network for Long-term Integrated Care (RNCCI) comprises several Units for Integrated Continuous Care (UCCIs) that provide medical, nursing, and rehabilitation care. This study aimed to evaluate the demographic and medical characteristics of patients admitted to the RNCCI, their patterns of medication use, and factors associated with polypharmacy. An observational, retrospective, cross-sectional, multicenter study was performed. This study population consisted of 180 patients. Polypharmacy status was divided into two groups: non-polypharmacy (taking ≤ 4 drugs) and polypharmacy (taking ≥ 5 drugs). Bivariate analysis and multivariate logistic regression analysis were used to determine the influence of predictor factors such as demographic and medical characteristics on the polypharmacy status during the UCCI stays. This study population (mean age of 78.4 ± 12.3 years, range 23-102 years, 59% female) was prescribed a median of 8 medications. Approximately 89.4% of the patients were taking ≥ 5 drugs, demonstrating that polypharmacy is highly prevalent in Portuguese RNCCI residents of the eight UCCIs studied. A subsequent analysis with multivariate logistic regression found that polypharmacy status was significantly associated with the unit of internment (facility) when compared to facility E with H and with the Charlson Comorbidity Index (CCI). The high prevalence of polypharmacy and the associated factors show that it is urgent to improve pharmacotherapy regimens through periodic monitoring and review of patients' therapeutic lists, an area in which pharmacists play a very important role.

Using PIM-Taiwan, PRISCUS, and Beers criteria to assess potentially inappropriate medication use among older adults with 90-day rehospitalization: a population-based study in Taiwan

Background: Multimorbidity and polypharmacy increase the risk of hospitalization in older adults receiving potentially inappropriate medication (PIM). The current study compared the ability of PIM-Taiwan, PRISCUS, and Beers criteria to predict 90-day rehospitalization in older patients with and without PIM. Methods: The retrospective cohort study used Taiwan's Longitudinal Health Insurance Database to retrieve quarterly information about prescribed medication for adults aged ≥65 years hospitalized between 2001 and 2018. We analyzed the association of PIM with 90-day rehospitalization using logistic regression. Results: The study cohort included 206,058 older adults (mean age: 72.5 years). In the analysis, 133,201 (64.6%), 97,790 (47.5%), and 147,450 (71.6%), were identified as having PIM exposure in PIM-Taiwan, PRICUS, and Beers criteria, respectively. PIM-Taiwan criteria found exposure to PIM affecting the cardiovascular (adjusted OR [aOR] 1.37, 95% confidence interval [CI] = 1.32-1.41), gastrointestinal (aOR 1.26, 95% CI = 1.23-1.30), central nervous (aOR 1.11, 95% CI = 1.08-1.14), and respiratory (aOR 1.16, 95% CI = 1.12-1.20) systems significantly increased the risk of 90-day rehospitalization, after adjustment for covariates. In PRISCUS criteria, exposure to PIM affecting the respiratory (aOR 1.48, 95% CI = 1.41-1.56), central nervous (aOR 1.12, 95% CI = 1.09-1.15), and cardiovascular (aOR 1.20, 95% CI = 1.16-1.24) systems significantly increased the risk. In Beers criteria, exposure to PIM affecting the cardiovascular (aOR 1.37, 95% CI = 1.32-1.41), gastrointestinal (aOR 1.38, 95% CI = 1.35-1.42), central nervous (aOR 1.18, 95% CI = 1.15-1.21), endocrine (aOR 1.10, 95% CI = 1.06-1.15), and respiratory (aOR 1.09, 95% CI = 1.04-1.13) systems significantly increased the risk. Patients with 90-day rehospitalization had higher rates of the potentially harmful drug-drug interaction (DDI) pairs of serotonin syndrome (n = 19; 48.8%), QT prolongation (n = 4; 30.8%), extrapyramidal symptoms (EPS) (n = 102; 24.5%), and hypokalemia (n = 275; 20.1%). Conclusion: Beers criteria was more efficient in predicting 90-day rehospitalization among older adults experiencing PIM in Taiwan than either PIM-Taiwan or PRISCUS. The risk of 90-day rehospitalization was associated with the potentially harmful DDI classes of serotonin syndrome, QT prolongation, EPS, and hypokalemia.

Adverse drug reactions in the ambulatory internal patients at the emergency department: Focus on causality assessment and drug-drug interactions

A non-interventional retrospective study in ambulatory patients was conducted at the emergency department of the Division of internal medicine. In 2 months, 266 suspected adverse drug reactions (ADRs) were identified in 224/3453 patients (6.5 %). In 158/3453 patients (4.6 %), an ADR was the reason for emergency department visit and in 49 patients (1.4 %), ADRs led to hospitalisation. A causality assessment algorithm was developed, which included Naranjo algorithm and levels of ADR recognition by the treating physician and the investigators. Using this algorithm, 63/266 ADRs (23.7 %) were classified as "certain", whereas using solely the Naranjo score calculation, only 19/266 ADRs (7.1 %) were assessed as "probable" or "certain", and the rest of ADRs (namely, 247/266 = 92.9 %) were assessed as "possible". There were 116/266 (43.6 %) ADRs related to potential drug-drug interactions (DDIs), stated in at least one of the literature sources used. Based on the causality relationship, the rate of the clinically expressed DDIs was 19.0 %, or 12/63 "certain" ADR cases. Of these, 10 cases presented serious DDI-related ADRs. In summary, ADR causality assessment based exclusively on Naranjo algorithm demonstrated low sensitivity at an ambulatory emergency setting. Additional clinical judgment, including the opinion of the treating physician, proved necessary to avoid under-rating of the causality relationship, and enabled the determination of clinically expressed DDIs.

Prevalence of Drug-Drug Interactions in Older Community-Dwelling Individuals: A Systematic Review and Meta-analysis

BACKGROUND

Drug-drug interactions (DDIs) can lead to medication-related harm, and the older population is at greatest risk. We conducted a systematic review and meta-analysis to estimate DDI prevalence and identify common DDIs in older community-dwelling adults.

METHODS

PubMed and EMBASE were searched for observational studies published between 01/01/2010 and 10/05/2021 reporting DDI prevalence in community-dwelling individuals aged ≥ 65 years. Nursing home and inpatient hospital studies were excluded. Study quality was assessed using the Joanna Briggs Institute critical appraisal tool. Meta-analysis was performed using a random-effects model with logit transformation. Heterogeneity was evaluated using Cochran's Q and I². DDI prevalence and 95% confidence intervals (CIs) are presented. All analyses were performed in R (version 4.1.2).

RESULTS

There were 5144 unique articles identified. Thirty-three studies involving 17,011,291 community-dwelling individuals aged ≥ 65 years met inclusion criteria. Thirty-one studies reported DDI prevalence at the study-participant level, estimates ranged from 0.8% to 90.6%. The pooled DDI prevalence was 28.8% (95% CI 19.3-40.7), with significant heterogeneity (p < 0.10; I² = 100%; tau² = 2.13) largely explained by the different DDI identification methods. Therefore, 26 studies were qualitatively synthesised and seven studies were eligible for separate meta-analyses. In a meta-analysis of three studies (N = 1122) using Micromedex^®, pooled DDI prevalence was 57.8% (95% CI 52.2-63.2; I² = 69.6%, p < 0.01). In a meta-analysis of two studies (N = 809,113) using Lexi-Interact^®, pooled DDI prevalence was 30.3% (95% CI 30.2-30.4; I² = 6.8%). In a meta-analysis of two studies (N = 947) using the 2015 American Geriatrics Society Beers criteria^®, pooled DDI prevalence was 16.6% (95% CI 5.6-40.2; I² = 97.5%, p < 0.01). Common DDIs frequently involved cardiovascular drugs, including ACE inhibitor-potassium-sparing diuretic; amiodarone-digoxin; and amiodarone-warfarin.

CONCLUSIONS

DDIs are prevalent among older community-dwelling individuals; however, the methodology used to estimate these events varies considerably. A standardised methodology is needed to allow meaningful measurement and comparison of DDI prevalence.

Impact of suspected adverse drug reactions on mortality and length of hospital stay in the hospitalised patients: a meta-analysis

PURPOSE

To estimate the risk of mortality and length of stay in hospitalised patients who have experienced suspected adverse drug reactions (ADRs) as compared to patients who did not experience suspected ADRs.

METHODS

A systematic literature search was conducted on databases for observational and randomised controlled studies conducted in any inpatient setting that reported deaths and/or length of hospital stay in patients who had suspected ADRs and did not have suspected ADRs during hospitalisation. PRISMA guidelines were strictly followed during the review. The methodological quality of included studies was assessed using a tool designed by Smyth et al. for the studies of adverse drug reactions. The meta-analytic summary of all-cause mortality was estimated using odds ratio-OR (95% CI) and length of stay using mean difference-MD (95% CI). Both outcomes were pooled using a random effect model (DerSimonian and Laird method). Subgroup and meta-regression were performed based on study variables: study design, age group, study ward, study region, types of suspected ADRs (ADR_Ad-suspected ADRs that lead to hospitalisation and ADR_In-suspected ADRs that occur following hospitalisation), study duration, sample size and study period. The statistical analysis was conducted through the 'Review manager software version 5.4.1 and JASP (Version 0.14.1)'.

RESULTS

After screening 475 relevant articles, 55 studies were included in this meta-analysis. Patients having suspected ADRs had reported significantly higher odds of all-cause mortality [OR: 1.50 (95% CI: 1.21-1.86; I² = 100%) than those patients who did not have suspected ADRs during hospitalisation. Study wards, types of suspected ADRs and sample size were observed as significant predictors of all-cause mortality (p < 0.05). Patients having suspected ADRs had reported significantly higher mean difference in hospital stay [MD: 3.98 (95% CI: 2.91, 5.05; I² = 99%) than those patients who did not have suspected ADRs during hospitalisation. Types of suspected ADRs and study periods were observed as significant predictors of length of stay (p < 0.05).

CONCLUSION

Suspected ADRs significantly increase the risk of mortality and length of stay in hospitalised patients.

SYSTEMATIC REVIEW REGISTRATION

CRD42020176320.

Drug-related hospital admissions in older adults: comparison of the Naranjo algorithm and an adjusted version of the Kramer algorithm

PURPOSE

Drug-related admissions (DRAs) are an important cause of preventable harm in older adults. Multiple algorithms exist to assess causality of adverse drug reactions, including the Naranjo algorithm and an adjusted version of the Kramer algorithm. The performance of these tools in assessing DRA causality has not been robustly shown. This study aimed to evaluate the ability of the adjusted Kramer algorithm to adjudicate DRA causality in geriatric inpatients.

METHODS

DRAs were assessed in a convenience sample of patients admitted to the acute geriatric wards of an academic hospital. DRAs were identified by expert consensus and causality was evaluated using the Naranjo and the adjusted Kramer algorithms. Positive agreement with expert consensus was calculated for both algorithms. A multivariable logistic regression analysis was performed to explore determinants for a DRA.

RESULTS

A total of 218 geriatric inpatients was included of whom 65 (29.8%) experienced a DRA. Positive agreement was 72.3% (95% confidence interval (CI), 59.6-82.3%) and 100% (95% CI, 93.0-100%) for the Naranjo and the adjusted Kramer algorithm, respectively. Diuretics were the main culprits and most DRAs were attributed to a fall (n = 18; 27.7%). A fall-related principal diagnosis was independently associated with a DRA (odds ratio 20.11; 95% CI, 5.60-72.24).

CONCLUSION

The adjusted Kramer algorithm demonstrated a higher positive agreement with expert consensus in assessing DRA causality in geriatric inpatients compared to the Naranjo algorithm. Our results further support implementation of the adjusted Kramer algorithm as part of a standardized DRA assessment in older adults.

Emergency room admissions induced by drug-drug interactions in the elderly: a cross-sectional study

The elderly people are increasingly exposed to polymedication and therefore to the risks of drug–drug interactions (DDIs). However, there are few data available on the clinical consequences of these drug combinations. We investigated the impact of the various DDIs classified as severe in terms of emergency admissions in the elderly. A cross‐sectional study was conducted using information from the emergency department admissions of Bordeaux University Hospital between September 2016 and August 2017. Events of interest were frequency of concomitant uses of interacting drugs that are contraindicated or warned against and frequency of emergency admissions due to contraindicated or warned against concomitant uses of interacting drugs. Five thousand, eight hundred sixty (5860) admissions to the emergency department were analyzed. A total of 375 (6.4%) contraindicated or warned against concomitant uses were identified, including 163 contraindicated (43.5%) and 212 warned against (56.5%). Reason for admission appeared likely related to the underlying DDI in 58 cases. Within these, 36 admissions were assessed as probably due to a DDI (0.6% of hospitalizations) and 22 as certainly (0.4% of hospitalizations). Of these, there were 24 (45%) admissions related to a long QT syndrome (LQTS), nine (16%) related to a drug overdose, and eight (14%) related to a hemorrhage. An antidepressant was involved in 22 of the 24 cases of LQTS. Seven of the eight cases of hemorrhage involved the antithrombotic agents / non‐steroidal anti‐inflammatory drugs combination. Elderly patients admitted to emergency departments are particularly exposed to high‐risk potential DDIs. These drug combinations lead mainly to LQTS and involve certain antidepressants.

Development of an Electronic Tool to Assess Patient Preferences in Geriatric Polypharmacy (PolyPref)

PURPOSE

Medical decision-making in older adults with multiple chronic conditions and polypharmacy should include the individual patient's treatment preferences. We developed and pilot-tested an electronic instrument (PolyPref) to elicit patient preferences in geriatric polypharmacy.

PATIENTS AND METHODS

PolyPref follows a two-stage direct approach to preference assessment. Stage 1 generates an individual preselection of relevant health outcomes and medication regimen characteristics, followed by stage 2, in which their importance is assessed using the Q-sort methodology. The feasibility of the instrument was tested in adults aged ≥70 years with ≥2 chronic conditions and regular intake of ≥5 medicines. After the assessment with PolyPref, the patients rated the tool with regard to its comprehensibility and usability and assessed the accuracy of the personal result. Evaluators rated the patients' understanding of the task.

RESULTS

Eighteen short-term health outcomes, 3 long-term health outcomes, and 8 medication regimen characteristics were included in the instrument. The final population for the pilot study comprised 15 inpatients at a clinic for geriatric rehabilitation with a mean age of 80.6 (± 6.0) years, a median score of 28 (range 25-30) points on the Mini-Mental State Examination, and a mean of 11.6 (± 3.6) regularly taken medicines. Feedback by the patients and the evaluators revealed ratings in favor of understanding and comprehensibility of 86.7% to 100%. The majority of the patients stated that their final result summarized the most important aspects of their pharmacotherapy (93.3%) and that its ranking order reflected their personal opinion (100%). Preference assessment took an average of 35 (± 8.5) min, with the instrument being handled by the evaluator in 14 of the 15 participants.

CONCLUSION

Preference assessment with PolyPref was feasible in older adults with multiple chronic conditions and polypharmacy, offering a new strategy for the standardized evaluation of patient priorities in geriatric pharmacotherapy.

Hospital admissions to geriatric ward related to adverse drug events: a cross-sectional study from the Czech Republic

Background Geriatric patients represent a vulnerable population in terms of adverse drug events (ADEs). Objective The aims of this study were to determine the prevalence and preventability of hospital admissions to a geriatric ward related to ADEs, to identify medications involved in these ADEs and to describe potential preventability aspects of ADE-related admissions. Setting University Hospital Hradec Králové, Czech Republic. Methods This cross-sectional study evaluated acute hospital admissions to the geriatric ward of University Hospital Hradec Králové over a period of nine months (April-December 2017). Medication reviews were performed in order to identify ADE-related hospital admissions. Causality was assessed using the World Health Organization-Uppsala Monitoring Centre criteria. Modified Schumock-Thornton algorithm was used to assess the preventability of ADEs. Main outcome measure 9-month-prevalence of ADE-related hospital admissions. Results A total of 366 hospital admissions were included. The 9-month-prevalence of ADE-related hospital admissions was 11.75% [95% confidence interval 8.45-15.05]. Antithrombotic agents and diuretics represented the most common medication classes associated with ADEs (30.2% each). Electrolyte disturbances and gastrointestinal haemorrhages and ulcerations were the most frequently observed ADEs associated with hospital admission. Out of 43 ADE-related hospitalisations, 23 (53.5%) were considered potentially preventable. Conclusion The contribution of ADEs to hospital admission to the geriatric ward was not negligible. Our results also suggest that 53.5% of identified ADE-related admissions could be potentially prevented. This finding demonstrates just how important the research on the preventability of medication-related hospitalisations is. Further studies and implementations are still needed aiming to minimize the risk of medication-related harm.

Treatment, Persistent Symptoms, and Depression in People Infected with COVID-19 in Bangladesh

Background: Coronavirus disease (COVID-19) has affected people's lives globally. While important research has been conducted, much remains to be known. In Bangladesh, initial treatment (self-administered, hospitalized), persistent COVID-19 symptoms ("long COVID-19"), and whether COVID-19 leads to changes in mental state, such as depressive symptoms, of people are not known. This study aimed to examine treatment, persistent symptoms, and depression in people who had been infected with COVID-19 in Bangladesh. Methods: A cross-sectional survey was conducted on 1002 individuals infected with COVID-19 (60% male; mean age = 34.7 ± 13.9; age range = 18-81 years), with data taken over a one-month period (11 September 2020 to 13 October 2020). A self-reported online questionnaire was used to collect data on socio-demographics, lifestyle, COVID-19 symptoms (during and beyond COVID-19), medication (over-the-counter or doctor-prescribed), and depression (assessed using the Patient Health Questionnaire (PHQ-9)). Results: Twenty-four percent of participants self-medicated with over-the-counter medicine when they were first diagnosed with COVID-19. Self-medication was higher among female vs. male respondents (29.6% vs. 20.2%, respectively, p = 0.002). A minority (20%) reported that they experienced persistent COVID-like symptoms after recovering from COVID-19. The most reported persistent symptoms were diarrhea (12.7%) and fatigue (11.5%). Forty-eight percent of participants were categorized as having moderate to severe depression. Based on multivariate regression analysis, depression during COVID-19 was positively associated with lower family income, poor health status, sleep disturbance, lack of physical activity, hypertension, asthma/respiratory problems, fear of COVID-19 re-infection, and persistent COVID-19 symptoms. Conclusions: The findings suggest a need for appropriate interventions for COVID-19 patients to promote physical and mental wellbeing.

Risk of Hospitalization Associated with Cardiovascular Medications in the Elderly Italian Population: A Nationwide Multicenter Study in Emergency Departments

Background: There is a significant gap in knowledge addressing cardiovascular (CV) medications safety in elderly. In this context, our purposes were to define clinical and pharmacological characteristics of outpatients’ adverse drug events (ADEs) related to CV medications leading to emergency department (ED) visits in the elderly Italian patients according to different age groups, and to evaluate the risk of hospitalization associated to ADEs in this population.

Methods: A multicentre, retrospective study was performed on reports of suspected ADEs collected between 2007–2018 in 94 EDs involved in the MEREAFaPS Study. Elderly patients who experienced one or more CV medications-related ADEs leading to ED visit were selected. Patients’ characteristics, suspected (ATC classes B and C) and concomitant drugs, and ADE description were collected. Elderly patients were stratified into three age groups (65–74, 75–84, and ≥85 years) and compared to adults (18–64 years). Logistic regression analyses were used to estimate the reporting odds ratios (RORs) with 95% confidence intervals (CIs) of ADE-related hospitalization adjusting for sex, presence of two or more suspected drugs, concomitant drugs, and one or more comorbidities.

Results: Among elderly, 16,926 reports of suspected ADE related to CV medications were collected, and 6,694 (39.5%) resulted in hospitalization. Patients were mostly female, Caucasians, and middle-old (75–84). 78.9% of patients were treated with only one suspected drug, and 71.9% and 47.1% reported concomitant medications and comorbidities, respectively. Compared to adults, risk of hospitalization was significantly higher for middle-old and oldest-old patients exposed to vitamin K antagonists (1.29 [1.09–1.52] and 1.56 [1.30–187]), direct thrombin inhibitors (3.41 [1.44–8.08] and 4.12 [1.67–10.17]), antiplatelets (1.51 [1.26–1.81] and 2.09 [1.71–2.57]), and beta-blockers (1.89 [1.38–2.59 and 2.31 [1.60–3.35]). Overall, a higher risk of hospitalization was observed for renin-angiotensin system inhibitors (1.32 [1.04–1.68], 1.65 [1.32–2.06], and 2.20 [1.70–2.85]), presence of two or more concomitant drugs, and concomitant conditions.

Conclusion: Our real-world findings underline relevant safety aspects of CV medications in the elderly Italian population. ED clinicians must always consider the higher risk of hospitalization related to the use of CV drugs in elderly, particularly in oldest-old ones, for antiarrhythmics, beta-blocking agents, renin-angiotensin system inhibitors, antiplatelets, and anticoagulants.

Antibiotic allergy as a cause of hospitalization in adults: a hospital-based study in Ukraine

Background:

Antibiotic allergy is an important clinical and social-economical issue.

Objective:

The main objectives of this study were to determine the incidence, causative drugs, and risk groups of antibiotic allergy as a reason for hospitalization. The secondary objective was to evaluate the treatment of antibiotic allergy through the identification of drug related problems (DRPs).

Methods:

This retrospective hospital-based study was carried out in one of Lviv city hospitals (Ukraine) from January 2015 to December 2017. Patients with antibiotic allergy as a cause for hospitalization were included in this study.

Results:

In this study the incidence of antibiotic allergy was 2.0% (95%CI 1.6:2.4) of all admissions to the Unit that provides special medical care for adult inpatients with allergy diseases and allergy reactions. The mean age of patients was 48.5 years (SD=17.0; range 18-83 years) with female predominance (78.2%; 95%CI 68.9:85.2). Antibiotic hypersensitivity reactions manifested as urticaria with angioedema (52.5%; 95%CI 42.3:62.5), urticaria (36.6%; 95%CI 27.8:46.8) or angioedema (10.9%; 95%CI 5.6:18.7). Beta-lactams (48.5%; 95%CI 38.5:58.7), fluoroquinolones (13.9%; 95%CI 7.8%:22.2%) and macrolides (7.9%; 95%CI 3.5:15.0) were specified as the main causative drugs. All patients during hospitalization (a mean of 8.2 days; SD=2.2; range 2-13 days) took at least 3 medicines (a mean of 5.4 medicines per patient; SD=1.2; range 3-12 medicines). The total number of identified DRPs was 400, a mean of 4.0 DRPs per patient (SD=1.8). The most frequently identified type of DRPs was inappropriate route of drug administration (25.0%; 95%CI 20.8:29.5). This was followed by duplicate prescriptions (23.5%; 95%CI 19.4:28.0) and insufficient frequency of drug administration (19.0%; 95%CI 15.3:23.2). Potential drug-drug interactions and inappropriate drug prescriptions each accounted for 16.0% (95% CI 12.6:20.0) of all DRPs. Comparing all above items in 2015, 2016 and 2017 showed no statistically significant changes (p>0.05).

Conclusions:

Antibiotic allergy is a common reason for admissions. The treatment of antibiotic allergy is associated with numerous DRPs. Our results could be useful for development of strategies for improving the safety and quality of pharmacotherapy.

Self-administration of medications for chronic diseases and drug-related hospital admissions in elderly patients at a Thai hospital

Background Studies of self-administered medications associated with hospital admissions are limited. Objective This study aimed to identify drug-related hospital admissions among elderly patients with diabetes, hypertension and chronic obstructive pulmonary disease and its association with self-administered medications. Method This was a prospective study of 335 patients admitted to a district hospital in Thailand from October 2018 to April 2019. The patients were divided into two groups: one with self-administered medication and the other with caregiver-administered medication. Pharmaceutical Care Network Europe V8.02-defined drug-related problems were identified. Those that conformed to the Hallas contribution and causality criteria were deemed drug-related hospital admissions and causes of the problems were examined. Main outcome measure An association between self-administration of medications and hospital admission was determined using a multivariable logistic regression analysis. Results The prevalence of drug-related hospital admissions was 20.6% (95% confidence interval, CI 16.4-25.3%) as an overall and was significantly higher in the self-administration group (25.4%) than in the caregiver administration group (12.7%). Among the drug-related hospital admissions in the self-administration and caregiver administration groups respectively, 71.7 and 62.5% were preventable, 63.2 and 37.7% were caused by patient themselves, and 26.3 and 37.5% were from adverse drug reactions. Medical conditions frequently caused by the patients included the exacerbation of chronic obstructive pulmonary disease due to using inhalers less than prescribed or administering drugs in the wrong manner in the self-administration group and hypoglycemia due to a long interval between insulin injection and meal consumption in the caregiver administration group. Compared to caregiver-administered medications, self-administration of medications increased the odds of hospital admission by approximately two-fold (adjusted odds ratio, OR 2.24, 95% CI 1.13-4.43). Other independent risk factors included the use of five or more medications a day (OR 2.65, 95% CI 1.16-6.07), the presence of underlying chronic obstructive pulmonary disease (OR 2.11, 95% CI 1.05-4.23) and self-medication (OR 2.59, 95% CI 1.12-5.99). Conclusion Self-administered medication was associated with hospital admissions in elderly patients with chronic diseases. To prevent problems, priority should be given to interventions to ensure the appropriate administration of inhaled medications for chronic obstructive pulmonary disease and antihyperglycemic agents.

The development of a scoring and ranking strategy for a patient-tailored adverse drug reaction prediction in polypharmacy

Only few applications are currently dealing with personalized adverse drug reactions (ADRs) prediction in case of polypharmacy. The study aimed to develop a patient-tailored ADR web application, considering characteristics from 734 drugs and relevant patient related factors. The application was designed in Python using a scoring and ranking system based on frequency and severity, computed for each ADR and expressed through an online platform. A neural networks algorithm was used for predicting the severity of ADRs. The application inputs are: age, gender, drugs, relevant pathologies. The outputs are: an overall severity profile (hospitalization and mortality risk), a stratified risk on specific ADR groups and a sorted list of the most important ADRs depending on frequency and severity. The Severity prediction model validation resulted in 79.7–85.1% Area Under the Receiver Operating Characteristic Curve Score, which lies in the good cut-off of 75–90%. The program offers a complex view regarding the ADR profile of a given patient and could be used by the physician and clinical pharmacist during patient safety monitoring, for a coherent therapy choice or medication adjustment, due to the good therapy coverage and the inclusion of relevant patient comorbidities.

Iatrogenesis and neurological manifestations in the elderly

Older people are often exposed to polypharmacy in a multimorbidity context. Inappropriate polypharmacy is often harmful, increasing the risk of inappropriate prescriptions and therefore adverse drug events (ADEs). Five to 20% of all hospital admissions are related to ADE in older people, among which 40 to 70% could be prevented. However, identifying ADEs and drug-related admissions in the elderly is challenging because ADEs often present as common geriatric problems such as falls, delirium, which might be due to the aging process, underlying diseases, and/or medications. In the pharmacovigilance database of the World Health Organization, drug-related neurological manifestations are the third reported cause of ADEs in the elderly, and neurological drugs are the third leading class of medications involved in ADEs. We must therefore be particularly vigilant, both in our prescriptions but also in our diagnoses to avoid prescribing inappropriate treatments and detect ADEs. Even though multiple pharmacologic changes occur in the elderly (absorption, distribution, drug metabolism and excretion), most of medications are still often prescribed at the same daily dosage as in young adults. When prescribing any drug for old patients, we should remember that daily intake should be adapted to these specificities, keeping in mind the old well-known aphorism "start low, go slow". In this review, we describe the main drug-related neurological manifestations (drug-induced movement disorders, falls, seizures, delirium, hypoglycemia, stroke, hyponatremia, peripheral neuropathy and myopathy, and serotonin syndrome) and the main drugs associated with neurological manifestations (dopamine receptor blocking agents, antithrombotics, anticholinergics, beta-lactams, antidepressants, benzodiazepines, mood stabilizers).

Methods to Assess Patient Preferences in Old Age Pharmacotherapy - A Systematic Review

PURPOSE

The aim of this systematic review was to identify methods used to assess medication preferences in older adults and evaluate their advantages and disadvantages with respect to their applicability to the context of multimorbidity and polypharmacy.

MATERIAL AND METHODS

Three electronic databases (PubMed, Web of Science, PsycINFO) were searched. Eligible studies elicited individual treatment or outcome preferences in a context that involved long-term pharmacological treatment options. We included studies with a study population aged ≥ 65 years and/or with a mean or median age of ≥ 75 years. Qualitative studies, studies assessing preferences for only two different treatments, and studies targeting preferences for life-sustaining treatments were excluded. The identified preference measurement methods were evaluated based on four criteria (time budget, cognitive demand, variety of pharmacological aspects, and link with treatment strategies) judged to be relevant for the elicitation of patient preferences in polypharmacy.

RESULTS

Sixty articles met the eligibility criteria and were included in the narrative synthesis. Fifty-five different instruments to assess patient preferences, based on 24 different elicitation methods, were identified. The most commonly applied preference measurement techniques were "medication willingness" (description of a specific medication with inquiry of the participant's willingness to take it), discrete choice experiments, Likert scale-based questionnaires, and rank prioritization. The majority of the instruments were created for disease-specific or context-specific settings. Only three instruments (Outcome Prioritization Tool, a complex intervention, "MediMol" questionnaire) dealt with the broader issue of geriatric multimorbidity. Only seven of the identified tools showed somewhat favorable characteristics for a potential use of the respective method in the context of polypharmacy.

CONCLUSION

Up to now, few instruments have been specifically designed for the assessment of medication preferences in older patients with multimorbidity. To facilitate valid preference elicitation in the context of geriatric polypharmacy, future research should focus on suitable characteristics of existing techniques to develop new measurement approaches for this increasingly relevant population.

Use of prescription drugs in the older adult population-a nationwide pharmacoepidemiological study

PURPOSE

Multi-morbidity and polypharmacy are common among older people. It is essential to provide a better understanding of the complexity of prescription drug use among older adults to optimise rational pharmacotherapy. Population-based utilisation data in this age group is limited. Using the Danish nationwide health registries, we aimed to characterise drug use among Danish individuals ≥ 60 years.

METHODS

This is a descriptive population-based study assessing drug prescription patterns in 2015 in the full Danish population aged ≥ 60 years. The use of specific therapeutic subgroups and chemical subgroups and its dependence on age were described using descriptive statistics. Profiles of drug combination patterns were evaluated using latent class analysis.

RESULTS

We included 1,424,775 residents (median age 70 years, 53% women). Of all the older adults, 89% filled at least one prescription during 2015. The median number of drug groups used was five per person. The most used single drug groups were paracetamol and analogues (34%), statins (33%) and platelet aggregation inhibitors (24%). Eighteen drug profiles with different drug combination patterns were identified. One drug profile with expected use of zero drugs and 11 drug profiles expected to receive more than five different therapeutic subgroup drugs were identified.

CONCLUSION

The use of drugs is extensive both at the population level and increasing with age at an individual level. Separating the population into different homogenous groups related to drug use resulted in 18 different drug profiles, of which 11 drug profiles received on average more than five different therapeutic subgroup drugs.

Understanding adverse drug-related emergency department visits: development of a conceptual model through a systematic review

Background

The burden of adverse drug event (ADE)-related emergency department (ED) visits is increasing despite several preventive measures. The objective of this paper was to develop and validate a conceptual model for a better understanding of ADE-related ED visits and to guide the design and implementation of effective interventions.

Methods

The development of the model involved a systematic review of the literature using PubMed and Embase databases. Studies reporting the risk factors associated with ADE-related ED visits were included. The methodological qualities of the included studies were assessed using the Mixed Methods Appraisal Tool (MMAT). The model was mapped and validated using face and content validity by an expert panel. Deficiencies and targeted interventions were identified, and steps for the design and implementation were recommended.

Results

The literature search generated 1361 articles, of which 38 were included in the review; 41 risk factors associated with ADE-related ED visits were identified. All factors were mapped, and the model was validated through face and content validity. The model consisted of six concepts related to sociodemographic factors, clinical factors, ADE-related to ED visits, ADE while in the ED, outcomes, and consequences. Interventions could be targeted at the factors identified in each concept to prevent ADE-related ED burden.

Conclusion

A conceptual model to guide the successful design and implementation of strategies to prevent ADE-related ED visits and the occurrence of ADE at ED was developed. Clinicians should take these factors into consideration to prevent untoward events, especially when treating high-risk patients.

Barriers and enablers for deprescribing among older, multimorbid patients with polypharmacy: an explorative study from Switzerland

Background

Polypharmacy is an increasing problem, leading to increased morbidity and mortality, especially in older, multimorbid patients. Consequently, there is a need for reduction of polypharmacy. The aim of this study was to explore attitudes, beliefs, and concerns towards deprescribing among older, multimorbid patients with polypharmacy who chose not to pursue at least one of their GP’s offers to deprescribe.

Methods

Exploratory study using telephone interviews among patients of a cluster-randomized study in Northern Switzerland. The interview included a qualitative part consisting of questions in five pre-defined key areas of attitudes, beliefs, and concerns about deprescribing and an open explorative question. The quantitative part consisted of a rating of pre-defined statements in these areas.

Results

Twenty-two of 87 older, multimorbid patients with polypharmacy, to whom their GP offered a drug change, did not pursue all offers. Nineteen of these 22 were interviewed by telephone. The 19 patients were on average 76.9 (SD 10.0) years old, 74% female, and took 8.9 (SD 2.6) drugs per day. Drugs for acid-related disorders, analgesics and anti-inflammatory drugs were the three most common drug groups where patient involvement and the shared-decision-making (SDM) process led to the joint decision to not pursue the GPs offer. Eighteen of 19 patients fully trusted their GP, 17 of 19 participated in SDM even before this study and 8 of 19 perceived polypharmacy as a substantial burden. Conservatism/inertia and fragmented medical care were the main barriers towards deprescribing. No patient felt devalued as a consequence of the deprescribing offer. Our exploratory findings were supported by patients’ ratings of predefined statements.

Conclusion

We identified patient involvement in deprescribing and coordination of care as key issues for deprescribing among older multimorbid patients with polypharmacy. GPs concerns regarding patients’ devaluation should not prevent them from actively discussing the reduction of drugs.

Trial registration

ISRCTN16560559.

Electronic supplementary material

The online version of this article (10.1186/s12875-019-0953-4) contains supplementary material, which is available to authorized users.

Hospitalisation and morbidity due to adverse drug reactions in elderly patients: a single-centre study

BACKGROUND

Adverse drug reaction (ADR) is a leading but under-recognised cause of illness, particularly in frail subjects with multiple comorbidities.

AIM

To investigate the frequency, patterns and outcomes of ADR as a cause of hospitalisation in elderly patients admitted to an internal medicine ward.

METHODS

We performed a retrospective observational study including every patient aged over 65 years who was admitted to our department during a 12-month period. Patients admitted to short-stay (<24 h) observation unit were excluded.

RESULTS

ADR accounted for 106 of total 1750 recorded admissions, which constituted a proportion of 6.1% (95% confidence interval 5.0-7.3%). The median age of patients was 83.5 (78.0-87.0) years and 56.6% were on polypharmacy. A total of 170 ADR was recorded with 45.3% of subjects experiencing concomitantly more than one ADR from a single molecule. Diuretics were the most commonly imputed molecules (30 events, 17.6%), followed by antithrombotics (25 events, 14.7%) and central nervous system-active drugs (16 events, 9.4%). Interactions were judged responsible for 39 cases of ADR (36.8%). An unfavourable outcome was observed in about one-third of patients (37.7%). Among those subjects, 11 (10.4%) died and 29 (27.4%) had residual disability.

CONCLUSION

ADR are a common cause of hospital admission in elderly patients and are often associated with adverse outcomes. Our data underline the need of appropriate strategies aimed at identifying high-risk patients and avoiding potentially preventable drug toxicities.

Risk of Drug-Drug Interactions in Out-Hospital Drug Dispensings in France: Results From the DRUG-Drug Interaction Prevalence Study

Introduction: Drug interactions could account for 1% of hospitalizations in the general population and 2-5% of hospital admissions in the elderly. However, few data are available on the drugs concerned and the potential severity of the interactions encountered. We thus first aimed to estimate the prevalence of dispensings including drugs Contraindicated or Discommended because of Interactions (CDI codispensings) and to identify the most frequently involved drug pairs. Second, we aimed to investigate whether the frequency of CDI codispensings appeared higher or lower than the expected for the drugs involved. Methods: We carried out a study using a random sample of all drugs dispensings registered in a database of the French Health Insurance System between 2010 and 2015. The distribution of the drugs involved was described considering active principles, detailing the 20 most frequent ones for both contraindicated or discommended codispensings (DCs). To investigate whether the frequency of CDI codispensings appeared higher or lower than the expected for the drugs involved, we developed a specific indicator, the Drug-drug interaction prevalence study-score (DIPS-score), that compares for each drug pair the observed frequency of codispensing to its expected probability. The latter is determined considering the frequencies of dispensings of the individual drugs constituting a pair of interest. Results: We analyzed 6,908,910 dispensings: 13,196 (0.2%) involved contraindicated codispensings (CCs), and 95,410 (1.4%) DCs. For CCS, the most frequently involved drug pair was "bisoprolol+flecainide" (n = 5,036); four out of five of the most represented pairs involved cardiovascular drugs. For DCS, the most frequently involved drug pair was "ramipril+spironolactone" (n = 4,741); all of the five most represented pairs involved cardiovascular drugs. The drug pair involved in the CC with the highest score value was "citalopram+hydroxyzine" (DIPS-score: 3.7; 2.9-4.6); that with the lowest score was "clarithromycin+simvastatin" (DIPS-score: 0.2; 0.2-0.3). DIPS-score median value was 0.4 for CCs and 0.6 for DCs. Conclusion: This high prevalence of CDI codispensings enforces the need for further risk-prevention actions regarding drug-drug interactions (DDIs), especially for arrhythmogenic or anti-arrhythmic drugs. In this perspective, the DIPS-score we develop could ease identifying the interactions that are poorly considered by clinicians/pharmacists and targeting interventions.

Using Electronic Health Records to Identify Adverse Drug Events in Ambulatory Care: A Systematic Review

OBJECTIVE

We identified the methods used and determined the roles of electronic health records (EHRs) in detecting and assessing adverse drug events (ADEs) in the ambulatory setting.

METHODS

We performed a systematic literature review by searching PubMed and Google Scholar for studies on ADEs detected in the ambulatory setting involving any EHR use published before June 2017. We extracted study characteristics from included studies related to ADE detection methods for analysis.

RESULTS

We identified 30 studies that evaluated ADEs in an ambulatory setting with an EHR. In 27 studies, EHRs were used only as the data source for ADE identification. In two studies, the EHR was used as both a data source and to deliver decision support to providers during order entry. In one study, the EHR was a source of data and generated patient safety reports that researchers used in the process of identifying ADEs. Methods of identification included manual chart review by trained nurses, pharmacists, and/or physicians; prescription review; computer monitors; electronic triggers; International Classification of Diseases codes; natural language processing of clinical notes; and patient phone calls and surveys. Seven studies provided examples of search phrases, laboratory values, and rules used to identify ADEs.

CONCLUSION

The majority of studies examined used EHRs as sources of data for ADE detection. This retrospective approach is appropriate to measure incidence rates of ADEs but not adequate to detect preventable ADEs before patient harm occurs. New methods involving computer monitors and electronic triggers will enable researchers to catch preventable ADEs and take corrective action.

Predictors of polypharmacy among elderly Thais with depressive and anxiety disorders: findings from the DAS study

BACKGROUND

Polypharmacy is a geriatric syndrome defined variously as the use of potentially inappropriate drugs and/or the concurrent use of multiple medications including prescription and over-the-counter drugs. An association has been shown between polypharmacy and physical health, increased morbidity and increased mortality. However, there is little information regarding the association between polypharmacy and physical disease, personality trait and mental health problems in elderly. The aim of this study was to investigate potential predictive psychosocial factors related to polypharmacy in elderly Thai people.

METHODS

The study analysed the secondary data from the Depressive Disorders, Anxiety Disorders, Suicide Risk and Associated Factors Among Elderly Thai People Program (DAS Study) which was funded by National Research Council of Thailand and conducted between January 2012 and April 2013. Demographic and baseline clinical characteristics including sex, age, education, living alone or with others, access to health care privilege and monthly income were described. The number of medication, physical diseases and mental health problems (i.e. depression, anxiety, and personality trait of neuroticism) were analyzed using descriptive statistics, chi-square and proportional odds logistic regression.

RESULTS

The 803 participants consumed an average of 2.13 prescribed medicines daily (SD 1.46, median = 2). The largest group used 3 medications (18.6%). Predictors found to be associated with polypharmacy in the logistic regression model included hypertension (OR = 1.985, 95% CI = 1.420-2.775), anxiety disorder (OR = 4.402, 95% CI = 2.630-7.367), number of diseases (OR = 2.140, 95% CI = 1.874-2.445), depressive disorder (OR = 1.470, 95% CI = 1.080-2.001), diabetes mellitus (OR = 1.864, 95% CI = 1.122-3.098) and dyslipidemia (OR = 0.511, 95%CI = 0.325-0.803).

CONCLUSIONS

The prevalence of polypharmacy among Thai elderly was relatively high compared to other related studies. Several aspects should be taken into consideration before starting an additional medication in elderly patients. In addition to the number of physical disease that leads to polypharmacy, general practitioners should be aware of anxiety, depression, and personality trait of neuroticism that may be related to polypharmacy. Early detection for such condition as well as non-pharmacological intervention could be one way to help reduce polypharmacy in the elderly.

The OptimaMed intervention to reduce inappropriate medications in nursing home residents with severe dementia: results from a quasi-experimental feasibility pilot study

BACKGROUND

Medication regimens in nursing home (NH) residents with severe dementia should be frequently reviewed to avoid inappropriate medication, overtreatment and adverse drug events, within a comfort care approach. This study aimed at testing the feasibility of an interdisciplinary knowledge exchange (KE) intervention using a medication review guidance tool categorizing medications as either "generally", "sometimes" or "exceptionally" appropriate for NH residents with severe dementia.

METHODS

A quasi-experimental feasibility pilot study with 44 participating residents aged 65 years or over with severe dementia was carried out in three NH in Quebec City, Canada. The intervention comprised an information leaflet for residents' families, a 90-min KE session for NH general practitioners (GP), pharmacists and nurses focusing on the medication review guidance tool, a medication review by the pharmacists for participating residents with ensuing team discussion on medication changes, and a post-intervention KE session to obtain feedback from team staff. Medication regimens and levels of pain and of agitation of the participants were evaluated at baseline and at 4 months post-intervention. A questionnaire for team staff explored perceived barriers and facilitators. Statistical differences in measures comparing pre and post-intervention were assessed using paired t-tests and Cochran's-Q tests.

RESULTS

The KE sessions reached 34 NH team staff (5 GP, 4 pharmacists, 6 heads of care unit and 19 staff nurses). Forty-four residents participated in the study and were followed for a mean of 104 days. The total number of regular medications was 372 pre and 327 post-intervention. The mean number of regular medications per resident was 7.86 pre and 6.81 post-intervention. The odds ratios estimating the risks of using any regular medication or a "sometimes appropriate" medication post-intervention were 0.81 (95% CI: 0.71-0.92) and 0.83 (95% CI: 0.74-0.94), respectively.

CONCLUSION

A simple KE intervention using a medication review guidance tool categorizing medications as being either "generally", "sometimes" or "exceptionally" appropriate in severe dementia was well received and accompanied by an overall reduction in medication use by NH residents with severe dementia. Levels of agitation were unaffected and there was no clinically significant changes in levels of pain. Staff feedback provided opportunities to improve the intervention.

Adverse Drug Reaction-Related Hospitalizations in Elderly Australians: A Prospective Cross-Sectional Study in Two Tasmanian Hospitals

INTRODUCTION

Adverse drug reactions (ADRs) have been commonly cited as a major cause of hospital admissions in older individuals. However, despite the apparent magnitude of this problem, there are limited prospective data on ADRs as a cause of hospitalization in elderly medical patients.

OBJECTIVES

The objective of this study was to evaluate the proportion, clinical characteristics, causality, severity, preventability, and outcome of ADR-related admissions in older patients admitted to two Tasmanian hospitals.

METHODS

We conducted a prospective cross-sectional study at the Royal Hobart and Launceston General Hospitals in Tasmania, Australia. A convenience sample of patients, aged 65 years and older, undergoing unplanned overnight medical admissions was screened. ADR-related admissions were determined through expert consensus from detailed review of medical records and patient interviews. The causality, preventability and severity of each ADR-related admission were assessed.

RESULTS

Of 1008 admissions, the proportion of potential ADR-related medical admissions was 18.9%. Most (88.5%) ADR-related admissions were considered preventable. Cardiovascular complaints (29.3%) represented the most common ADRs, followed by neuropsychiatric (20.0%) and renal and genitourinary disorders (15.2%). The most frequently implicated drug classes were diuretics (23.9%), agents acting on the renin angiotensin system (16.4%), β-blocking agents (7.1%), antidepressants (6.9%), and antithrombotic agents (6.9%). Application of the Naranjo algorithm found 5.8% definite, 70.1% probable, and 24.1% possible ADRs. ADR severity was rated moderate and severe in 97.9% and 2.1% of admissions, respectively. For most (93.2%) ADR-related admissions the ADR resolved and the patient recovered.

CONCLUSION

Hospitalization due to an ADR is a common occurrence in this older population. There is need for future studies to implement and evaluate interventions to reduce the risk of ADR-related admissions in elderly populations.

Mortality among patients due to adverse drug reactions that lead to hospitalization: a meta-analysis

PURPOSE

The aim of this study was to estimate the prevalence of mortality among patients due to adverse drug reactions that lead to hospitalisation (fatal ADR_Ad), to explore the heterogeneity in its estimation through subgroup analysis of study characteristics, and to identify system-organ classes involved and causative drugs for fatal ADR_Ad.

METHODS

We identified prospective ADR_Ad-related studies via screening of the PubMed and Google Scholar databases with appropriate key terms. We estimated the prevalence of fatal ADR_Ad using a double arcsine method and explored heterogeneity using the following study characteristics: age groups, wards, study region, ADR definitions, ADR identification methods, study duration and sample size. We examined patterns of fatal ADR_Ad and causative drugs.

RESULTS

Among 312 full-text articles assessed, 49 studies satisfied the selection criteria and were included in the analysis. The mean prevalence of fatal ADR_Ad was 0.20% (95% CI: 0.13-0.27%; I² = 93%). The age groups and study wards were the important heterogeneity modifiers. The mean fatal ADR_Ad prevalence varied from 0.01% in paediatric patients to 0.44% in the elderly. Subgroup analysis showed a higher prevalence of fatal ADR_Ad in intensive care units, emergency departments, multispecialty wards and whole hospitals. Computer-based monitoring systems in combination with other methods detected higher mortality. Intracranial haemorrhage, renal failure and gastrointestinal bleeding accounted for more than 50% of fatal ADR_Adcases. Warfarin, aspirin, renin-angiotensin system (RAS) inhibitors and digoxin accounted for 60% of fatal ADR_Ad.

CONCLUSIONS

ADR_Ad is an important cause of mortality. Strategies targeting the safer use of warfarin, aspirin, RAS inhibitors and digoxin could reduce the large number of fatal ADR_Adcases.

Adverse-Drug-Reaction-Related Hospitalisations in Developed and Developing Countries: A Review of Prevalence and Contributing Factors

Adverse drug reactions (ADRs) are one of the leading causes of hospital admissions and morbidity in developed countries and represent a substantial burden on healthcare delivery systems. However, there is little data available from low- and middle-income countries. This review compares the prevalence and characteristics of ADR-related hospitalisations in adults in developed and developing countries, including the mortality, severity and preventability associated with these events, commonly implicated drugs and contributing factors. A literature search was conducted via PubMed, Scopus, Web of Science, Embase, ProQuest and Google Scholar to find articles published in English from 2000 to 2015. Relevant observational studies were included. The median (with interquartile range [IQR]) prevalence of ADR-related hospitalisation in developed and developing countries was 6.3 % (3.3-11.0) and 5.5 % (1.1-16.9), respectively. The median proportions of preventable ADRs in developed and developing countries were 71.7 % (62.3-80.0) and 59.6 % (51.5-79.6), respectively. Similarly, the median proportions of ADRs resulting in mortality in developed and developing countries were 1.7 % (0.7-4.8) and 1.8 % (0.8-8.0), respectively. Commonly implicated drugs in both settings were antithrombotic, non-steroidal anti-inflammatory and cardiovascular drugs. Older age, female gender, number of medications, renal impairment and heart failure were reported to be associated with an increased risk for ADR-related hospitalisation in both settings while HIV/AIDS was implicated in developing countries only. The majority of ADRs were preventable in both settings, highlighting the importance of improving medication use, particularly in vulnerable patient groups such as the elderly, patients with multiple comorbidities and, in developing countries, patients with HIV/AIDS.

Categorization and association analysis of risk factors for adverse drug events

PURPOSE

Adverse drug events (ADE) are among the leading causes of morbidity and hospitalization. This review analyzes risk factors for ADE, particularly their categorizations and association patterns, the prevalence, severity, and preventability of ADE, and method characteristics of reviewed studies.

METHODS

Literature search was conducted via PubMed, Science Direct, CINAHL, and MEDLINE. A review was conducted of research articles that reported original data about specific risk factors for ADE since 2000. Data analyses were performed using Excel and R.

RESULTS

We summarized 211 risk factors for ADE, and grouped them into five main categories: patient-, disease-, medication-, health service-, and genetics-related. Among them, medication- and disease-related risk factors were most frequently studied. We further classified risk factors within each main category into subtypes. Among them, polypharmacy, age, gender, central nervous system agents, comorbidity, service utilization, inappropriate use/change use of drugs, cardiovascular agents, and anti-infectives were most studied subtypes. An association analysis of risk factors uncovered many interesting patterns. The median prevalence, preventability, and severity rate of reported ADE was 19.5% (0.29%~86.2%), 36.2% (2.63%~91%), and 16% (0.01%~47.4%), respectively.

CONCLUSIONS

This review introduced new categories and subtypes of risk factors for ADE. The broad and in-depth coverage of risk factors and their association patterns elucidate the complexity of risk factor analysis. Managing risk factors for ADE is crucial for improving patient safety, particularly for the elderly, comorbid, and polypharmacy patients. Some under-explored risk factors such as genetics, mental health and wellness, education, lifestyle, and physical environment invite future research.

Predictors of adverse drug reaction-related hospitalisation in Southwest Ethiopia: A prospective cross-sectional study

BACKGROUND

Adverse drug reactions (ADRs) are important causes of morbidity and mortality in the healthcare system; however, there are no studies reporting on the magnitude and risk factors associated with ADR-related hospitalisation in Ethiopia.

OBJECTIVES

To characterise the reaction types and the drugs implicated in admission to Jimma University Specialized Hospital, Southwest Ethiopia, and to identify risk factors associated with ADR-related hospitalisation.

METHODS

A prospective cross-sectional study was conducted from May 2015 to August 2016 among consenting patients aged ≥18 years consecutively admitted to medical wards taking at least one medication prior to admission. ADR-related hospitalisations were determined through expert review of medical records, laboratory tests, patient interviews and physical observation. ADR causality was assessed by the Naranjo algorithm followed by consensus review with internal medicine specialist. ADR preventability was assessed using Schumock and Thornton's criteria. Only definite and probable ADRs that provoked hospitalisation were considered. Binary logistic regression was used to identify independent predictors of ADR-related hospitalisation.

RESULTS

Of 1,001 patients, 103 (10.3%) had ADR-related admissions. Common ADRs responsible for hospitalisation were hepatotoxicity (35, 29.4%) and acute kidney injury (27, 22.7%). The drug classes most frequently implicated were antitubercular agents (45, 25.0%) followed by antivirals (22, 12.2%) and diuretics (19, 10.6%). Independent predictors of ADR-related hospitalisation were body mass index (BMI) <18.5 kg/m2 (adjusted odd ratio [AOR] = 1.69; 95% confidence interval [CI] = 1.10-2.62; p = 0.047), pre-existing renal disease (AOR = 2.84; 95%CI = 1.38-5.85, p = 0.004), pre-existing liver disease (AOR = 2.61; 95%CI = 1.38-4.96; p = 0.003), number of comorbidities ≥4 (AOR = 2.09; 95%CI = 1.27-3.44; p = 0.004), number of drugs ≥6 (AOR = 2.02; 95%CI = 1.26-3.25; p = 0.004) and history of previous ADRs (AOR = 24.27; 95%CI = 11.29-52.17; p<0.001). Most ADRs (106, 89.1%) were preventable.

CONCLUSIONS

ADRs were a common cause of hospitalisation. The majority of ADRs were preventable, highlighting the need for monitoring and review of patients with lower BMI, ADR history, renal and liver diseases, multiple comorbidities and medications. ADR predictors should be integrated into clinical pathways and pharmacovigilance systems.

Physicians' Non-Uniform Approach to Prescribing Drugs to Older Patients - A Qualitative Study

Multi-morbidity and polypharmacy are common in older patients and increase their susceptibility to adverse drug events and hospitalizations. Rational drug prescription is critical; however, little is known about physicians' perspectives on how to prescribe drugs for older patients. The aim of this study was to explore physicians' approach to prescribe drugs to older patients, including identifying the drugs that physicians perceive to be risk drugs for older patients and comparing them with established lists of potentially inappropriate medications. Short semi-structured interviews were conducted with 50 medical specialists in 23 different specialities throughout Denmark who had contact with older patients. Content analysis was performed to identify the relevant themes. Regardless of their medical or surgical background and how often they prescribed drugs for older patients in daily work, all physicians expressed a cautious approach when prescribing risk drugs. Despite their shared caution, physicians had different strategies for prescribing drugs to older patients. The following strategies were identified: (1) 'Start low, go slow', (2) 'Trial and error', (3) 'Dose reduction', and (4) 'Never prescribe'. The most frequently mentioned risk drugs considered to cause hospitalization were vitamin K antagonists, opioids and diuretics; these drugs are relatively highly consistent with established lists of PIMs. Physicians were relatively knowledgeable about risk drugs. Although the physicians agreed that a cautious approach was needed when prescribing drugs for older people, there was no consensus about how to best accomplish this in practice.

Drug-Related Harms in Hospitalized Medicare Beneficiaries: Results From the Healthcare Cost and Utilization Project, 2000-2008

OBJECTIVES

We examined drug harms in Medicare beneficiaries using the 2000-2008 data from the Nationwide Inpatient Sample Healthcare Cost and Utilization Project.

RESEARCH DESIGN

This is a cross-sectional study to examine the national estimates of potentially preventable drug-related hospitalizations and in-hospital adverse drug events identified with the International Classification of Diseases codes excluding intentional harms.

RESULTS

Hospitalizations related to drug poisoning constituted 0.8% of all Medicare hospitalizations. Annual hospital charges increased from $1.6 billion in 2000 to $4 billion in 2008. In-hospital adverse drug events were noted in 5.3% of all Medicare hospitalizations and increased by 90% from 2000 to 2008. Patients with extreme versus minor loss of function (odds ratio [OR], 2.96; 95% confidence interval [CI], 2.93-2.99) and with extreme versus minor likelihood of dying (OR, 2.30; 95% CI, 2.29-2.33) had increased odds of in-hospital adverse drug events after adjustment for age, sex, and race. The Medicare beneficiaries with more than 5 versus fewer than 5 listed diagnoses had greater odds of in-hospital adverse drug events (OR, 3.79; 95% CI, 3.76-3.82). Each additional diagnosis at discharge was associated with a 13% increase in odds of in-hospital death in the Medicare beneficiaries hospitalized with drug-related diagnoses and with 12% increase in odds of in-hospital death in the Medicare beneficiaries with in-hospital adverse events.

CONCLUSIONS

Potentially preventable drug harms are a growing clinical and financial burden. Comparative outpatient drug safety should be analyzed using Medicare claim databases. In-hospital management of drug safety should target patients with multimorbidity and functional decline.

Adverse drug events-Analysis of a decade. A Portuguese case-study, from 2004 to 2013 using hospital database

PURPOSE

The goal of this study was to characterise adverse drug events (ADE), including both adverse drug reaction (ADR) and accidental poisoning by drugs (AP), considering age, gender, length of stay (LOS), number of deaths and year, during the period 2004-2013. Additionally distributions of the ten's most frequent ADR and AP were characterized, considering age-group and gender.

METHODS

A retrospective descriptive nationwide study was conducted, based on the hospital discharges database in Portugal from 2004 to 2013, using ICD-9. Events were identified based on the following codes: from E930 to E949.9 and from E850 to E858.9.

RESULTS

A total of 9 320 076 patients were discharged within this period, with 133 688 patients (1.46%) having at least one ADE, 4% of them related with AP. The mean age of these patients was 63.79 years (SD 21.31), 54.50% were female and the mean LOS was 14.05 days (SD 22.19). Patient with AP had a mean age of 41.06 years (SD 34.05), 54.70% were female and LOS was 7.15 days (SD 19.42). We have identified 10.691 deaths that represent 8.00% from the total of patients with an ADE. The patients above 65 years were more affected by ADR and children below 18 were more affected by AP.

CONCLUSION

In the last decade an increasing trend of ADR were observed and an AP pattern relatively stable. Elderly people and children were the age groups most affected. Antibiotics (in ADR) and benzodiazepine-based tranquilizers (in AP) were the major problems. This is a huge, increasing and challenging problem. Further research, using individual and contextual risk factors should be developed to understand spatiotemporal variability, promoting tailored interventions, within and across countries.

Prevalence, risk factors and health outcomes associated with polypharmacy among urban community-dwelling older adults in multi-ethnic Malaysia

BACKGROUND

Polypharmacy has been associated with increased morbidity and mortality in the older population.

OBJECTIVES

The aim of this study was to determine the prevalence, risk factors and health outcomes associated with polypharmacy in a cohort of urban community-dwelling older adults receiving chronic medications in Malaysia.

METHODS

This was a baseline study in the Malaysian Elders Longitudinal Research cohort. The inclusion criteria were individuals aged ≥55years and taking at least one medication chronically (≥3 months). Participants were interviewed using a structured questionnaire during home visits where medications taken were reviewed. Health outcomes assessed were frequency of falls, functional disability, potential inappropriate medication use (PIMs), potential drug-drug interactions (PDDIs), healthcare utilisation and quality of life (QoL). Risk factors and health outcomes associated with polypharmacy (≥5 medications including dietary supplements) were determined using multivariate regression models.

RESULTS

A total of 1256 participants were included with a median (interquartile range) age of 69(63-74) years. The prevalence of polypharmacy was 45.9% while supplement users made up 56.9% of the cohort. The risk factors associated with increasing medication use were increasing age, Indian ethnicity, male, having a higher number of comorbidities specifically those diagnosed with cardiovascular, endocrine and gastrointestinal disorders, as well as supplement use. Health outcomes significantly associated with polypharmacy were PIMS, PDDIs and increased healthcare utilisation.

CONCLUSION

A significant proportion of older adults on chronic medications were exposed to polypharmacy and use of dietary supplements contributed significantly to this. Medication reviews are warranted to reduce significant polypharmacy related issues in the older population.

Hospital admissions due to adverse drug reactions in the elderly. A meta-analysis

INTRODUCTION

It is currently admitted that adverse drug reactions (ADRs) account for a great burden of disease. Of particular concern are ADR-induced hospital admissions, particularly in the elderly; they receive most of the medications and they are the most prone to develop ADRs. Therefore, our aim was to carry out a study of ADR-induced hospital admissions focused on the elderly population.

METHODS

For the purpose, a systematic review and meta-analysis was performed of those studies addressing ADR-induced hospital admissions in patients over 60 years of age. A computerized search of the literature was carried out in the main databases. The search spans from 1988 to 2015. A pooled prevalence figure was calculated with 95% CIs; heterogeneity was also explored.

RESULTS

The final number of selected articles was 42; all of them were published between January 1988 and August 2015. The overall average percentage of hospital admissions was 8.7% (95% CI, 7.6-9.8%). NSAIDs are one of the medication classes more frequently related to these admissions (percentages range from 2.3 to 33.3%). Inappropriate medication as a risk factor was studied in nine studies, four found a statistically significant relationship between those medications and hospital admissions.

CONCLUSIONS

Circa one in ten hospital admissions of older patients are due to ADRs. A great burden of disease is due to a few and identifiable medication classes; in most of the cases, the reactions are well known and probably preventable. A sense of purpose and determination is needed by health authorities to face this problem. Doctors, on their part, should be aware when prescribing some specific identifiable medications to these patients.

KEY POINTS

1. One in ten hospital admissions in older patients are due to ADRs; NSAIDs are the medications the most related with these admissions, followed by other common medications used in patients of this age, such as beta-blockers. 2. A great burden of disease is due to medications that are intended to cure or alleviate disease; this burden of disease is not only painful for the patients but also costly. 3. Identified risk factors are particular medication classes and polymedication. In most of the cases, reactions are probably preventable.

The risks of polypharmacy following spinal cord injury

OBJECTIVE

The purpose of this study was to examine the overall prevalence of polypharmacy within the spinal cord injury (SCI) population, the level of polypharmacy with respect to seven classes of high-risk drugs commonly used to treat secondary conditions in the SCI population, and the overall risks for drug-related problems (DRP) related to polypharmacy.

DESIGN

A retrospective case-control design.

SETTING

A commercially available claims dataset that included patient cases from 4800 hospitals in the USA between 2007 and 2009.

PARTICIPANTS

Individuals with tetraplegia, paraplegia, and those with SCI but not specified as either tetraplegia or paraplegia as well as a control population of randomly selected, age- and sex-matched individuals without a diagnosis of SCI.

OUTCOME MEASURES

The overall prevalence of polypharmacy, the prevalence of commonly prescribed high-risk medications, and the prevalence of reported DRPs.

RESULTS

Overall, the patients in the SCI population were prescribed significantly more medications than their control counterparts. There was a higher rate of individuals being prescribed medications from multiple high-risk classes (e.g. analgesic-narcotics, anticonvulsant, antidepressant, and skeletal muscle relaxer), as well as multiple medications within each class (e.g. multiple analgesic-narcotics). The SCI group had a higher incidence of DRPs.

CONCLUSION

Our results are some of the first to demonstrate the extent of polypharmacy in individuals with SCI, including commonly prescribed high-risk medications, leading to a higher rate of DPRs. The higher rate of polypharmacy and DRPs can impact rehabilitation goals and community integration following neurologic injury.

Effectiveness of medication review: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Medication review is often recommended to optimize medication use. In clinical practice it is mostly operationalized as an intervention without co-interventions during a short term intervention period. However, most systematic reviews also included co-interventions and prolonged medication optimization interventions. Furthermore, most systematic reviews focused on specific patient groups (e.g. polypharmacy, elderly, hospitalized) and/or on specific outcome measures (e.g. hospital admissions and mortality). Therefore, the objective of this study is to assess the effectiveness of medication review as an isolated short-term intervention, irrespective of the patient population and the outcome measures used.

METHODS

A literature search was performed in MEDLINE, EMBASE and Web of Science from their inception through September 2015. Randomized controlled trials (RCTs) with medication review as isolated short term intervention (<3 months) were included. There were no restrictions with regard to patient characteristics and outcome measures. One reviewer extracted and a second checked data. The risk of bias of studies was evaluated independently by two reviewers. A best evidence synthesis was conducted for every outcome measure used in more than one trial. In case of binary variables a meta-analysis was performed in addition to the best evidence synthesis, to quantify the effect.

RESULTS

Thirty-one RCTs were included in this systematic review (55% low risk of bias). A best evidence synthesis was conducted for 22 outcome measures. No effect of medication review was found on clinical outcomes (mortality, hospital admissions/healthcare use, the number of patients falling, physical and cognitive functioning), except a decrease in the number of falls per patient. However, in a sensitivity analysis using a more stringent threshold for risk of bias, the conclusion for the effect on the number of falls changed to inconclusive. Furthermore no effect was found on quality of life and evidence was inconclusive about the effect on economical outcome measures. However, an effect was found on most drug-related problems: medication review resulted in a decrease in the number of drug-related problems, more changes in medication, more drugs with dosage decrease and a greater decrease or smaller increase of the number of drugs.

CONCLUSIONS

An isolated medication review during a short term intervention period has an effect on most drug-related outcomes, minimal effect on clinical outcomes and no effect on quality of life. No conclusion can be drawn about the effect on economical outcome measures. Therefore, it should be considered to stop performing cross-sectional medication reviews as standard care.

Adverse drug reactions to anticoagulants in Spain: analysis of the Spanish National Hospital Discharge Data (2010-2013)

OBJECTIVE

To describe and analyse hospitalisations for adverse drug reactions (ADRs) involving anticoagulants. We also analysed the progress of the reactions over time, the factors related with ADRs.

DESIGN

A retrospective, descriptive, epidemiological study.

SETTING

This study used the Spanish National Hospital Discharge Database (Conjunto Mínimo Básico de Datos, CMBD), over a 4-year period.

PARTICIPANTS

We selected CMBD data corresponding to hospital discharges with a diagnosis of ADRs to anticoagulants (International Classification of Diseases-Ninth Revision, Clinical Modification (ICD-9-CM) code E934.2) in any diagnostic field during the study period.

MAIN OUTCOME MEASURES

We calculated the annual incidence of ADRs to anticoagulants according to sex and age groups. The median lengths of hospital stay and in-hospital mortality (IHM) were also estimated for each year studied. Bivariate analyses of the changes in variables according to year were based on Poisson regression. IHM was analysed using logistic regression models. The estimates were expressed as ORs and their 95% CI.

RESULTS

During the study period, 50 042 patients were hospitalised because of ADRs to anticoagulants (6.38% of all ADR-related admissions). The number of cases increased from 10 415 in 2010 to 13 891 in 2013. Cumulative incidence of ADRs to anticoagulants was significantly higher for men than women and in all age groups. An adjusted multivariate analysis revealed that IHM did not change significantly over time. We observed a statistically significant association between IHM and age, with the highest risk for the ≥85 age group (OR 2.67; 95% CI 2.44 to 2.93).

CONCLUSIONS

The incidence of ADRs to anticoagulants in Spain increased from 2010 to 2013, and was significantly higher for men than women and in all age groups. Older patients were particularly susceptible to being hospitalised with an adverse reaction to an anticoagulant.

Hospitalizations Due to Adverse Drug Events in the Elderly-A Retrospective Register Study

Adverse drug events (ADEs) are more likely to affect geriatric patients due to physiological changes occurring with aging. Even though this is an internationally recognized problem, similar research data in Finland is still lacking. The aim of this study was to determine the number of geriatric medication-related hospitalizations in the Finnish patient population and to discover the potential means of recognizing patients particularly at risk of ADEs. The study was conducted retrospectively from the 2014 emergency department patient records in Oulu University Hospital. A total number of 290 admissions were screened for ADEs, adverse drug reactions (ADRs) and drug-drug interactions (DDIs) by a multi-disciplinary research team. Customized Naranjo scale was used as a control method. All admissions were categorized into “probable,” “possible,” or “doubtful” by both assessment methods. In total, 23.1% of admissions were categorized as “probably” or “possibly” medication-related. Vertigo, falling, and fractures formed the largest group of ADEs. The most common ADEs were related to medicines from N class of the ATC-code system. Age, sex, residence, or specialty did not increase the risk for medication-related admission significantly (min p = 0.077). Polypharmacy was, however, found to increase the risk (OR 3.3; 95% CI, 1.5–6.9; p = 0.01). In conclusion, screening patients for specific demographics or symptoms would not significantly improve the recognition of ADEs. In addition, as ADE detection today is largely based on voluntary reporting systems and retrospective manual tracking of errors, it is evident that more effective methods for ADE detection are needed in the future.

Prevalence and characteristics of adverse drug reactions at admission to hospital: a prospective observational study

Aims

Adverse drug reactions (ADRs) contribute to poorer patient outcomes and additional burden to the healthcare system. However, data on the true burden, relevant types and drugs causing ADRs are lacking. The aim of this study was to determine the prevalence of ADR‐related hospitalization in the general adult population in Singapore and to investigate their characteristics.

Methods

We prospectively recruited 1000 adult patients with unplanned admission to a large tertiary‐care hospital. Two independent reviewers evaluated all suspected ADRs for causality, type, severity and avoidability. The prevalence of ADR‐related hospitalization was calculated based on ‘definite’ and ‘probable’ ADRs. Logistic regression was used to evaluate predictors for having an ADR at admission.

Results

The prevalence of all ADRs at admission was 12.4% (95% CI: 10.5–14.6%) and ADRs causing admission was 8.1% (95% CI: 6.5–10.0%). The most common ADRs were gastrointestinal‐related. The most common drug category causing ADRs were cardiovascular drugs. Patients with ADRs had a longer length of stay than those who did not (median 4 vs. 3 days, P = 1.70 × 10⁻³). About 30% of ADRs at admission were caused by at least one drug with a clinical annotation in the Pharmacogenomics KnowledgeBase (PharmGKB), suggesting that some of these ADRs may have been predicted by pharmacogenetic testing.

Conclusions

We have quantified the burden and characteristics of clinically impactful ADRs in the Singaporean general adult population. Our results will provide vital information for efforts in reducing ADRs through targeted vigilance, patient education and pharmacogenomics in Singapore.

Antibiothérapie du sujet âgé : On peut toujours mieux faire

Antimicrobials are among the most prescribed drugs and their prescription increases with age, due to frailty and accrued risk factors for acquiring infections. Antimicrobial prescription in elderly patients must not only account for the risk of toxicity due to drug overexposure, but also of treatment failure or promotion of antimicrobial resistance due to under-dosage. This paper reviews the main antimicrobial, pharmacokinetic and pharmacodynamic variations induced by aging, comorbidities and polypharmacy, and how to take them into account to optimize antimicrobial prescription in elders.

[Not Available]

AIM

To describe the serious adverse drug reactions (ADR) in elderly subjects aged over 65 years and assess their preventability.

METHODS

A retrospective study was conducted at the Regional Pharmacovigilance Center of Champagne-Ardenne (northeast of France) between January and May 2013. Patients aged over 65 years who presented a serious ADR notified to the Regional Pharmacovigilance Center were included in the study.

RESULTS

Over the study period, 100 subjects were included in the study. The sex ratio was 0.96. Twenty seven percent of serious ADR were preventable. Off-label use accounted for 20% and non-compliance for 5%. Bleeding events were the most common serious ADR (36%). The drugs most frequently involved in serious ADR were antithrombotic agents (31.4%).

CONCLUSION

More than a quarter of serious ADR were preventable. Off-label use and non-compliance are the main causes identified in the occurrence of preventable serious ADR.

Inappropriate prescribing of antithrombotic therapy in Ethiopian elderly population using updated 2015 STOPP/START criteria: a cross-sectional study

Background

Inappropriate use of antiplatelets and anticoagulants among elderly patients increases the risk of adverse outcomes. The aim of this study was to assess the prevalence of inappropriate prescribing of antithrombotic therapy in hospitalized elderly patients.

Methods

A retrospective cross-sectional, single-center study was conducted at the Gondar University Hospital. A total of 156 hospitalized elderly patients fulfilling the inclusion/exclusion criteria were included in the study. The Screening Tool for Older Person’s Prescription/Screening Tool to Alert doctors to Right Treatment criteria version 2 were applied to patients’ data to identify the total number of inappropriate prescribing (IPs) including potentially inappropriate medications and potential prescribing omissions.

Results

A total of 70 IPs were identified in 156 patients who met the inclusion criteria. Of these, 36 (51.4%) were identified as potentially inappropriate medications by the Screening Tool for Older Person’s Prescription criteria. The prevalence of IP per patient indicated that 58 of the 156 (37.2%) patients were exposed to at least one IP. Of these, 32 (55.2%) had at least one potentially inappropriate medication and 33 (56.9%) had at least one potential prescribing omission. Patients hospitalized due to venous thromboembolism (adjusted odds ratio [AOR] =29.87, 95% confidence interval [CI], 1.26–708.6), stroke (AOR =7.74, 95% CI, 1.27–47.29), or acute coronary syndrome (AOR =13.48, 95% CI, 1.4–129.1) were less likely to be exposed to an IP. An increase in Charlson comorbidity index score was associated with increased IP exposure (AOR =0.60, 95% CI, 0.39–0.945). IPs were about six times more likely to absent in patients prescribed with antiplatelet only therapy (AOR =6.23, 95% CI, 1.90–20.37) than those receiving any other groups of antithrombotics.

Conclusion

IPs are less common in elderly patients primarily admitted due to venous thromboembolism, stroke, and acute coronary syndrome, and those elderly patients prescribed with only antiplatelet. Patients with higher Charlson comorbidity index were, however, associated with increased IPs exposure. Our study may guide further research to reduce high-risk prescription of antithrombotics in the elderly.